For estimating the parameter information of target chirp signal within multiple chirp signal and noise,which is the conventional familiar model in signal processing,the stochastic resonance (SR) in over-damped bistable system driven by the multiple signals and noise was investigated.Using the energy aggregation on optimal fractional Fourier transform domain of chirp signals,the distorted output signals were filtered on optimal fractional Fourier transform (FrFT) domain,and a new signal-to-interference ratio (SIR) gain defined in optimal FrFT domain was proposed to describe the system performance,and used to observe the generalized SR phenomenon.The simulation results showed that interfering chirp signals could assist weak noise with particle jump,which is called coordinative SR phenomenon (CSR).Moreover, the detection performance of target chirp signal is improved.
